Abstract: Amino acid inhibitors extracted from bean dregs were studied. The results of IR spectrum of extracts showed that the main ingredient of extracts was amino acid, and the preferable extracting conditions were 125 ml 20% HCl and 10g bean dregs reacted 180 min, and composite amino acids content in extractors is 0.185 g/L. The results of corrosion inhibition performance from static weight loss showed that the types, temperature and concentration of acidic mediums had influence on corrosion inhibition remarkably. The corrosion inhibition efficiency of extracts was up to 97.8% in mud acid. The results of electrochemiscal performance of extracts indicated that corrosion potential of J55 steel shifted to negative direction both in hydrochloric acid and mud acid. The extracts is a cathodic corrosion inhibitor, can improve the circular-arc radius of notably in acidic mediums, and the corrosion inhibition effect is remarkable. It is practicable to extract inhibitors from bean dregs.